Re: [RFC PATCH 1/3] Unified trace buffer

From: Martin Bligh
Date: Wed Sep 24 2008 - 16:56:54 EST


> On Wed, 24 Sep 2008, Martin Bligh wrote:
>>
>> If we use 32 bits instead of 27, then the timestamp events are only
>> about once per second, which is probably fine for overhead ... ?
>
> You'd have them ONCE IN A BLUE MOON.
>
> If there is nothing going on, you don't need the timestamps at all.

Yeah, you're right - we can just mark it dirty, and 'pre-log' the timestamp
events when someone calls a reserve and we haven't logged anything
for more time than we can store. Did not think of that. Was only 5 bits
for us, not an extra 37, but still, is much better.

Is a 5-bit event id generic enough though?
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